The mobile framework allows web developers to natively target all
smartphone with a single codebase (JavaScript, HTML and CSS) by enabling a
Foreign Function Interface (FFI) to an embedded WebView or Webkit on the
device.

Appcelerator Titanium Mobile is a web based application framework
solutions allowing web developers to apply existing skills to create native
applications for iPhone and Android using the familiar JavaScript syntax.
Developers will also have to learn the extensive Titanium API. Wikipedia
notes that the term cross-compiler is misleading as the titanium engine
interprets the code during run time.